Laboratorium voor Biochemie, Fakulteit van de Landbouwwetenschappen-RUG, Coupure Links 533, B 9000 Gent, Belgium.
Plant Physiol. 1980 Jan;65(1):13-6. doi: 10.1104/pp.65.1.13.
Large doses of gamma-irradiation, given to air-dried pea seeds, inhibit the endomitotic DNA synthesis in pea epicotyls during germination in darkness. The cortex cells of the etiolated epicotyls reach only the 4 C DNA level, whereas cortex cells of unirradiated seeds reach the 8 C DNA level. Epicotyl elongation and cell elongation are also reduced.Application of gibberellic acid restores the endomitotic DNA synthesis and the cell elongation in epicotyls of irradiated seeds. The cortex cells reach again the 8 C DNA level in darkness.The results suggest that gamma-irradiation blocks endomitotic DNA synthesis and cell elongation by lowering the concentration of endogenous gibberellins.
大剂量的γ射线照射风干的豌豆种子，会抑制黑暗中萌发的豌豆上胚轴的有丝分裂 DNA 合成。在暗培养下，经γ射线照射的豌豆上胚轴的皮层细胞仅达到 4C 的 DNA 水平，而未经照射的种子的皮层细胞达到 8C 的 DNA 水平。上胚轴的伸长和细胞伸长也减少。赤霉素的应用恢复了照射种子上胚轴的有丝分裂 DNA 合成和细胞伸长。在黑暗中，皮层细胞再次达到 8C 的 DNA 水平。结果表明，γ射线通过降低内源性赤霉素的浓度来阻断有丝分裂 DNA 合成和细胞伸长。
